CLINICAL
PRE-OPERATIVE NUTRITION Any form of surgical procedure causes the body physiological stress, the extent to which depends on the severity of the surgery.1 Surgical procedures can have a profound impact on a patient’s nutritional status and this article sheds light on the importance of adequate nutrition in the lead up to surgery. Most surgical procedures do not require a specific diet to be followed prior to surgery other than a well-balanced and healthy diet. We should all be aiming to eat more fruit and vegetables, wholegrains, and oily fish,2 keeping the government Eatwell Guide in mind (see Figure 1). In the UK, it is recommended that we consume two portions of fish a week, with at least one portion (140g) from oily fish.4 We should also choose lean meats and low-fat dairy, as well as heart healthy fats such as olive oil and rapeseed oil. Saturated fat, alcohol and caffeine should be limited to recommended amounts. Most younger and middle-aged people in the UK consume above the recommended daily amount of protein;2 however, people who follow a vegan or vegetarian diet should make sure they are consuming adequate amounts of protein from plant-based sources such as lentils, chickpeas, peanuts, tofu, edamame beans. Elderly people and people with chronic illnesses do not always consume enough protein in their diet, which can lead to muscle loss and sarcopenia, so optimising protein intake prior to surgery is important.5 ESPEN guidelines suggest that healthy older people should have at least 1.0-1.2g of protein per kilogram of bodyweight per day, and those with acute or chronic illnesses may require as much as 1.5g of protein per kilogram of bodyweight per day.6 It’s important that patients are adequately hydrated in the lead up to their surgery to avoid dehydration, as this can cause post-operative complications.7
SPECIFIC DIETARY REQUIREMENTS
In some cases, specific dietary requirements apply. For example, before bariatric surgery, a supervised weightmanagement program is recommended. This involves patients following a verylow-calorie diet (sometimes referred to as a liver-shrinking diet) for several weeks. This dietary approach has been associated with a 10% weight loss and a 15-20% reduction in liver volume, making the surgery easier to perform.8 In addition, patients with diabetes require an individualised approach. The Joint British Diabetes Societies for Inpatient Care have released a specific set of recommendations for the management of adults with diabetes undergoing surgery and elective procedures. During the pre-operative stage, they recommend that clinicians should:9 • assess adequacy of glycaemic control against the urgency of procedure; • consider a referral to the diabetes specialist team; • identify other comorbidities with referral to appropriate teams for optimal management where necessary; • ensure availability of usual insulin and medications; • give the patient clear written instructions for any changes to their medication as well as fasting guidelines prior to admission; • ensure patients with diabetes are not placed on an evening list as this avoids prolonged starvation times.
Harriet Smith RD Freelance Dietitian and Health Writer Harriet is Founder of Surrey Dietitian providing private dietetic consultations and consultancy services, offering evidence-based nutritional advice, backed up by the latest research on food, health and disease. Harriet has written for national, consumer and industry media. www.surrey dietitian.co.uk @SurreyDietitian
REFERENCES Please visit the Subscriber zone at NHDmag.com
www.NHDmag.com August/September 2019 - Issue 147
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